Geologists Need to Know Geosteering

Here’s a pro-tip for aspiring geologists and their new-to-the-job peers:

Think engineering.

“One of the first roles for a geologist, for an operator, is likely to be very involved in drilling,” said Sam Noynaert, assistant professor of engineering at Texas A&M University.

“It would behoove geologists to get in on a course or two on drilling engineering,” he added.

Like many aspects of the industry, this need stems in large part from the widespread unconventional reservoir development spurred by hydraulic fracturing and horizontal drilling. Even though horizontal wellbores might not always be essential to production, no one would argue that directional drilling technology alone is what has made most unconventional plays economic, according to Noynaert, whose background includes drilling engineering in unconventional plays.

The key to horizontal effectiveness is geosteering, or guiding the bit along what have become continually extending laterals within precisely defined and generally narrow windows. The defining geological markers are ordinarily the top and bottom of the pay zone. Adding to the intrigue and challenge of the procedure is that these target areas are usually very deep in the subsurface.

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Here’s a pro-tip for aspiring geologists and their new-to-the-job peers:

Think engineering.

“One of the first roles for a geologist, for an operator, is likely to be very involved in drilling,” said Sam Noynaert, assistant professor of engineering at Texas A&M University.

“It would behoove geologists to get in on a course or two on drilling engineering,” he added.

Like many aspects of the industry, this need stems in large part from the widespread unconventional reservoir development spurred by hydraulic fracturing and horizontal drilling. Even though horizontal wellbores might not always be essential to production, no one would argue that directional drilling technology alone is what has made most unconventional plays economic, according to Noynaert, whose background includes drilling engineering in unconventional plays.

The key to horizontal effectiveness is geosteering, or guiding the bit along what have become continually extending laterals within precisely defined and generally narrow windows. The defining geological markers are ordinarily the top and bottom of the pay zone. Adding to the intrigue and challenge of the procedure is that these target areas are usually very deep in the subsurface.

This process is not for the weak of heart, considering that the geologist on the well must often make decisions on the fly as the ongoing flow of data are analyzed. Based on numerous discussions with involved personnel, Noynaert deduced that the thorny aspects of today’s geosteering activity can be broken into two primary issues.

The most common issue he noted was a lack of knowledge about basic drilling fundamentals by geologists, which led to an inability to understand the consequences of geology geosteering decisions on the ability to drill a well. Conversely, the drilling group should understand how their decisions impact the geologist.

The second was that the job performance metrics by which technical employees are measured, and thus tend to drive their decisions, are not well aligned between the disciplines.

Odd Coupling

Noynaert elaborated, noting that the fact that each group seldom understands the reasoning behind other teams’ decisions leads to a potentially inefficient and combative geosteering process.

Each discipline harbors different goals and measures of success, which each participant must understand in order to avoid placing the geosteering operation and, in turn, the well productivity at risk.

It’s widely recognized in the industry that geologists and engineers are not the same breed of cat.

“Sometimes it’s like two different cultures,” Noynaert remarked. “It’s human nature to try to perform to your metrics, and I don’t think people understand this.”

He commented on a graduate-level horizontal drilling course he taught last year in which he hosted a guest speaker to present a short course in geosteering. “For someone with experience, I learned a lot and thought to myself that this needs to be taught for both engineers and geologists.”

“As someone who teaches drilling, I’ve had less than 20 geology students in seven years,” he lamented. “I’ve found no geosteering courses being offered nor basic drilling courses being required, even though a brand new geologist is likely to be out on a rig or assisting with the operations side.”

Time is of the essence.

Lateral lengths are continuing to increase to the point that 20,000 feet likely will soon become just another day in paradise.

“When you’re drilling 5,000-foot laterals in the Barnett, torque and drag is not such a big deal,” Noynaert said. “But when you’re drilling 30,000 feet, say, in the Bakken, it’s a huge difference and you’re pushing the envelope. Wells are starting to push or extend the technology limits.”

What To Know

So, you ask, what specifically do geologists need to know if they’re destined – at least temporarily – to take on the role of geosteering guru?

In addition to their geological and geophysical knowledge and expertise, Noynaert said the geologist must understand three aspects of the field and the engineering teams’ roles. They are:

The physical fundamentals of drilling a well, including torque and drag, hydraulics and basic directional drilling.

The metrics by which the engineering and wellsite teams are measured, such as cost per foot, days per well or hole interval, and drilling authority for expenditures.

The consequences of geological team decisions on drilling operations.

He emphasized that the fundamentals of drilling he refers to do not encompass such things as mud mixing, drill bit identification and related drilling basics. Rather, they are essentially the physics involved in what is enmeshed in the process of drilling a horizontal or extended reach well. As a rule, such topics don’t receive their due until upper level petroleum courses.

It’s essential that the meatier material gets disseminated somehow, somewhere, he said. This includes topics such as maintaining a stable wellbore, circulating and cleaning the hole and much more.

“In short, they are topics which almost no geoscience major will ever study in school and thus will be forced to learn on their own during their career,” Noynaert stated.